1. Field of the Invention
Embodiments of the invention relate generally to flat panel displays. More specifically, embodiments of the invention relate to a light emitting module of a flat panel display backlight.
2. Description of the Related Art
Generally, a liquid crystal display apparatus includes a display panel displaying an image using light, and a light providing assembly providing the light to the display panel. The display panel includes a first substrate including a switching element driving a pixel, and a second substrate opposite to the first substrate. A liquid crystal layer is disposed between the first and second substrates. The second substrate usually includes a color filter which is used for the display apparatus to display the color image.
The light providing assembly includes a light emitting module, and a plurality of optical elements to effectively provide emitted light to the display panel. In the past, light emitting modules typically used a cold cathode fluorescent lamp (CCFL) or an external electrode fluorescent lamp (EEFL). However, recently, such modules have instead made increasing use of light emitting diodes (LEDs) having relatively high luminance. The LEDs are electrically and physically connected to a printed circuit board to receive a light source driving signal from a light source driver, so that the LEDs emit light.
It is known that the relative positions of the light emitting module and optical element have an effect on the luminance of the light providing assembly. For example, as a distance between a light guide plate (optical element) and the light emitting module is increased, more light may be lost, as less light is transmitted to the light guide plate. This may result in decreased luminance.
In contrast, when the light emitting module is disposed close to the optical element to minimize the loss of light provided from the light emitting module, the light guide plate may be expanded and deformed due to heat from the light emitting module. The expansion and deformation of the light guide plate can result in detrimental effects such as separation of the light emitting module from the printed circuit board, which can lead to disconnection of the light emitting module from its power source.